1. Field of the Invention
The present invention relates to a method and apparatus for producing communication articles such as postcards, envelopes or the like. Particularly, the present invention relates to a method and apparatus for producing communication articles such as postcards, envelopes or the like in which display surfaces for information or the like are separably bonded by heating them through a synthetic resin film or the like in order to conceal information such as correspondence or a print display medium, and then mail it.
2. Description of the Related Art
An example of prior art related to a method and apparatus for producing such communication articles is the invention disclosed in Japanese Patent Laid-Open No. 2-106556.
In the invention disclosed in this publication, information is printed on a predetermined portion of both upper and lower sheets, and an intermediate sheet having portions at both sides thereof which permit both sheets to be separably bonded is then interposed between both sheets during the process of putting the sheets one on top the other so that both sheets are separably bonded with the adhesive intermediate sheet therebetween to form one product.
A continuous sheet is used for both the upper and lower sheets and is cut to each sheet's predetermined size after the upper and lower sheets are bonded with the intermediate sheet therebetween to produce a communication article such as postcards or the like.
However, in the above invention, since the work of cutting the continuous sheets with the film therebetween to each sheet's predetermined size is carried out by employing the tensile force produced by a difference between the transfer velocities of two rolls, the upper and lower sheets can each be cut, but the intermediate sheet made of a synthetic resin film cannot be smoothly cut even if perforations are provided therein. Since the intermediate sheet made of a synthetic film cannot be smoothly cut, therefore, there is the possibility of an error in the operation occurring. Even if no error occurs, there is the problem that an unnecessary portion of the film will be protrude from the upper and lower sheets due to the distortion produced at the edge of the cut intermediate sheet.
Further, in the above-mentioned apparatus, one continuous sheet is cut by a cutter into sheet portions which are used as the upper and lower sheets, and the intermediate sheet is then interposed between the upper and lower sheets. Thus the position of the intermediate sheet interposed between the two sheets is easily deviated. This results in the danger of producing defective products.